I cast platinum in a large shop with an induction casting machine. The temp sensor was replaced and doesn’t seem to read the temps properly. We cast steel in the same machine and it’s working like normal.
The platinum pieces are easily broken after casting. They kind of have a soft, gummy texture inside the broken area. Is my temp too high? Too low? I’ve recast both ways and am not getting consistent enough results to determine what is the right way to go. Any help is greatly appreciated!
It sounds like contamination from the steel. Use a new crucible and all new platinum and you should be good.
Oh! I meant that we use the machine for steel, but not the same crucible. I included the steel info just to say that it is operating normally with steel, but is not operating normally with platinum. I have tried new crucible as well, though. Thank you for your reply!
So my husband Tim who has worked at a platinum foundry has questions for you.
What alloy are you using? What parameters on your flask temps? What investment? Are you using an inert gas bath?
It’s important not to reuse the failed brittle platinum too. Try with all new metal if you haven’t already done that. Make sure there is no chance of contamination with anything. I’m guessing you’re probably using the right temps.
It was the temp after all! We were spinning at just a little too high. Our machine’s sensor is not reading correctly, but we were able to get more consistent results with a few more tests. Thanks for your replies!
I’m so glad that it all worked out. We’re here to help.
Jo